Last week, I hosted a dinner for participants in our Parkinson’s Progression Markers Initiative (PPMI) study. Over a delicious Vermont beverage, one participant told me he had just been invited to join a trial testing a new treatment. (PPMI studies Parkinson’s progression but does not test treatments.)
He was diagnosed about a year ago and hadn’t yet started Parkinson’s medication — uncommon but sought after by some trials. He was considering it, though the medical center was a long drive.
“How do I know it’s a ‘good’ trial?” he asked. “There are so many out there, and I want to use my time and energy toward the best.”
It’s a great question. Study participants are valued partners in advancing new treatments, but it is a commitment.
A “good” trial isn’t just one with strong science. It’s one that fits your life, your comfort level and your goals. What feels right will differ from person to person.
Here are some of the factors we discussed — and that you may want to consider when evaluating a clinical trial.
Mechanism and Previous Results
Start by understanding what the treatment is designed to do. What is it trying to change in the body? What is the scientific rationale?
Some therapies aim to slow disease progression by reducing clumps of alpha-synuclein protein or by fighting inflammation. Others test devices or technologies to improve symptoms, such as walking or balance.
In early-stage trials (Phase I), researchers focus primarily on safety. By later stages, there should already be safety data — and sometimes early signs of benefit.
The study team should be able to help you understand the treatment’s mechanism, rationale and any previous results. You can search for peer-reviewed publications (how scientists share findings) on pubmed.gov or look for summaries on sites like ours or Parkinson’s News Today. Then, think about what resonates with you and your disease.
Eligibility requirements vary. Some trials require that you not yet be on Parkinson’s medication; others require a stable dose. If you’re unsure whether you qualify, ask.
Placebo and Open-Label Extension
Most drug trials include randomization to drug or placebo. A placebo is an inactive tablet (often called a “sugar pill”) used so researchers can compare outcomes between groups.
Many studies offer a 50 percent chance of receiving placebo, though that can vary. Studies testing multiple doses, for example, offer a lower chance of placebo, such as one in three.
Some trials include an open-label extension, allowing all participants — including those who received placebo — to access the active treatment after the blinded portion ends. If the therapy shows signs of impact, this allows more volunteers to access it and enables researchers to gather more long-term data.
You can ask the study team:
- What is the chance I will receive placebo?
- Is there an open-label extension?
- What happens after the study ends?
And remember, you can leave a trial at any time, for any reason. Your medical care will not be affected. Participation is always voluntary.
Impact on Your Care Plan
Joining a trial could mean changes in current or future care. For many, that is the appeal (offering something new and maybe better). But for some symptoms, your doctor may have other options. Being in a trial may mean that you can’t or need to delay testing those approaches. If you are considering deep brain stimulation, for example, timing can matter.
Certain studies — particularly gene or cell therapy trials — may also limit your ability to join future trials. These one-time treatments may make you ineligible for other research later.
Ask yourself or your doctor:
- What could I try outside of a trial?
- What might I gain by joining now?
- What might I delay?
- Will this trial prevent me from joining others in the future?
Travel, Time and Compensation
Participating in research shouldn’t create undue hardship.
Most trials will reimburse travel and lodging costs. Some also cover expenses for a study partner. If you need additional support — for travel, accessibility or scheduling — speak up. The study team may be able to help.
Compensation for time and procedures varies. Ethics boards set limits so that payment doesn’t pressure participation, but time-consuming visits or invasive procedures should be fairly compensated.
If something feels unclear or insufficient, ask. These conversations are part of partnership.
Defining “Good” for You
Before deciding, you might ask yourself:
- Do I understand the purpose of this study?
- Am I comfortable with the known risks — and the unknowns?
- Does the schedule fit my life?
- How does this trial fit into my larger treatment plan?
- Do I feel heard and respected by the study team?
A “good” trial is one you understand. One where your questions are answered. One that aligns with your priorities — now and in the future.
If you’re considering a clinical trial, know that you have agency. Ask questions. Take your time. Talk with your doctor and your loved ones.
And as the gentleman at dinner reminded, your time and energy matter. Choosing where to invest them is entirely up to you.
Cheers.
